The atmospheric carbon-dioxide (CO2) levels are increasing continuously due to rapid industrial growth. Major industrial sites like thermal power plants, oil refineries, and other processing plants such as cement, steel, aluminum, and the like cause most of the carbon-dioxide (CO2) emission into the environment. The increased level of atmospheric carbon-dioxide (CO2) is considered to be one of the main causes for global warming. In order to combat global warming, several precautionary measures are required. The precautionary measures include the use of low carbon or carbon free energy sources like nuclear and wind, and other alternative methods such as capture and sequestration of carbon-dioxide (CO2).
Various conventional processes such as absorption, adsorption, membrane separation cryogenic separation, and the like can be used for capturing carbon-dioxide (CO2). From the afore-stated conventional processes, the adsorption process is advantageous due to its enhanced carbon-dioxide (CO2) capture capacity, lower regeneration energy, and low operational cost which provide easy retrofit to existing systems.
The adsorption process is carried out in the presence of an adsorbent, and the efficiency of the adsorption process is dependent upon a composition of the adsorbent used.
However, there are certain limitations associated with the conventional adsorption process, for example:                poor multi-cycle adsorption capacity;        requires high regeneration temperature for decomposing the stable intermediate species (for example KAl(CO3)2(OH)2) formed on the surface of the adsorbent during the adsorption of carbon-dioxide (CO2); thereby increasing the overall energy demand of the adsorption process; and        the efficiency of removal/capture of carbon-dioxide (CO2) from a gas stream decreases with every cycle of regeneration of the adsorbent.        
There is, therefore, felt a need for an alternative to capture carbon-dioxide (CO2) from a gas stream and obviate the above mentioned drawbacks.